UPDATE: Hantavirus Spreads In Yosemite

The death of a West Virginia resident marks the third fatality from Hantavirus Pulmonary Syndrome contracted in Yosemite National Park. In June, the victim stayed in the "Signature Tents" at Curry Village, where officials previously believed the disease was isolated.

On Thursday, however, Yosemite National Park officials announced that the Hantavirus was not confined solely to this area. One infected person stayed in several High Sierra camps in Yosemite in July. After this case was confirmed, officials more than doubled their estimate of visitors at risk of contracting the deadly mouse-borne disease from 10,000 to 22,000 to include others who stayed at these locations.

The warning extends worldwide. More than 2,500 people from 39 different countries stayed at  these sites in Yosemite between June 10 and August 24, when the outbreak occured.

Symptoms of Hantavirus include fatigue, fever, body aches and difficulty breathing, and normally appear two to four weeks after exposure. Although there is no cure for the hanta virus, early detection and oxygen treatments can help increase patients' chances of survival, according to CDC spokeswoman Lola Russell.

There have been eight reported cases of Hantavirus among Yosemite visitors to date. Deer mice are the most common carriers of Hantavirus with 12 percent of their population positive for the disease. To help prevent against Hantavirus, follow the Centers for Disease Control and Prevention's recommended precautions.